Q3 of 12 Page 110

Find the area of base and radius of a cylinder if its curved surface area is 660 sqcm and height is 21 cm

Area of base of cylinder = π × r2


Curved surface area of cylinder(CSA) = 2π × r × h


Here, CSA = 660 sqcm, h = 21 cm, r = ?


CSA = 2π × r × h


660 = 2π × r × 21



r = 5 cm


Area of base = π × r2


= 3.14 × 25 × 25


= 78.5 cm2


Area of the base is 78.5 cm2 and radius is 5 cm


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(1) r = 7 cm, h = 10 cm


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Find the volume of the cylinder if height (h) and radius of the base (r) are as given below.

(1) r = 10.5 cm, h = 8 cm


(2) r = 2.5 m, h = 7 m


(3) r = 4.2 cm, h = 5 cm


(4) r = 5.6 cm, h = 5 cm